diff --git a/i18n.gemspec b/i18n.gemspec
index a6b55ea5..8dcf493f 100644
--- a/i18n.gemspec
+++ b/i18n.gemspec
@@ -25,6 +25,9 @@ Gem::Specification.new do |s|
   s.require_path = 'lib'
   s.required_rubygems_version = '>= 1.3.5'
   s.required_ruby_version = '>= 2.3.0'
+  s.post_install_message = if RUBY_VERSION < '3.2'
+                              "PSA: I18n will be dropping support for Ruby < 3.2 in the next major release (April 2025), due to Ruby's end of life for 3.1 and below (https://endoflife.date/ruby). Please upgrade to Ruby 3.2 or newer by April 2025 to continue using future versions of this gem."
+  end
 
   s.add_dependency 'concurrent-ruby', '~> 1.0'
 end
diff --git a/lib/i18n.rb b/lib/i18n.rb
index 2980f025..9a6a535d 100644
--- a/lib/i18n.rb
+++ b/lib/i18n.rb
@@ -19,6 +19,7 @@ module I18n
   RESERVED_KEYS = %i[
     cascade
     deep_interpolation
+    skip_interpolation
     default
     exception_handler
     fallback
@@ -161,7 +162,7 @@ def eager_load!
     # or <tt>default</tt> if no translations for <tt>:foo</tt> and <tt>:bar</tt> were found.
     #   I18n.t :foo, :default => [:bar, 'default']
     #
-    # *BULK LOOKUP*
+    # <b>BULK LOOKUP</b>
     #
     # This returns an array with the translations for <tt>:foo</tt> and <tt>:bar</tt>.
     #   I18n.t [:foo, :bar]
@@ -180,7 +181,7 @@ def eager_load!
     # E.g. assuming the key <tt>:salutation</tt> resolves to:
     #   lambda { |key, options| options[:gender] == 'm' ? "Mr. #{options[:name]}" : "Mrs. #{options[:name]}" }
     #
-    # Then <tt>I18n.t(:salutation, :gender => 'w', :name => 'Smith') will result in "Mrs. Smith".
+    # Then <tt>I18n.t(:salutation, :gender => 'w', :name => 'Smith')</tt> will result in "Mrs. Smith".
     #
     # Note that the string returned by lambda will go through string interpolation too,
     # so the following lambda would give the same result:
@@ -192,7 +193,7 @@ def eager_load!
     # always return the same translations/values per unique combination of argument
     # values.
     #
-    # *Ruby 2.7+ keyword arguments warning*
+    # <b>Ruby 2.7+ keyword arguments warning</b>
     #
     # This method uses keyword arguments.
     # There is a breaking change in ruby that produces warning with ruby 2.7 and won't work as expected with ruby 3.0
@@ -264,7 +265,8 @@ def interpolation_keys(key, **options)
     def exists?(key, _locale = nil, locale: _locale, **options)
       locale ||= config.locale
       raise Disabled.new('exists?') if locale == false
-      raise I18n::ArgumentError if key.is_a?(String) && key.empty?
+      raise I18n::ArgumentError if (key.is_a?(String) && key.empty?) || key.nil?
+
       config.backend.exists?(locale, key, options)
     end
 
diff --git a/lib/i18n/backend/base.rb b/lib/i18n/backend/base.rb
index 7ca9c28a..0c59cd72 100644
--- a/lib/i18n/backend/base.rb
+++ b/lib/i18n/backend/base.rb
@@ -54,8 +54,9 @@ def translate(locale, key, options = EMPTY_HASH)
         end
 
         deep_interpolation = options[:deep_interpolation]
+        skip_interpolation = options[:skip_interpolation]
         values = Utils.except(options, *RESERVED_KEYS) unless options.empty?
-        if values && !values.empty?
+        if !skip_interpolation && values && !values.empty?
           entry = if deep_interpolation
             deep_interpolate(locale, entry, values)
           else
@@ -151,7 +152,14 @@ def resolve(locale, object, subject, options = EMPTY_HASH)
           result = catch(:exception) do
             case subject
             when Symbol
-              I18n.translate(subject, **options.merge(:locale => locale, :throw => true))
+              I18n.translate(
+                subject,
+                **options.merge(
+                  :locale => locale,
+                  :throw => true,
+                  :skip_interpolation => true
+                )
+              )
             when Proc
               date_or_time = options.delete(:object) || object
               resolve(locale, object, subject.call(date_or_time, **options))
@@ -244,7 +252,7 @@ def load_file(filename)
         # Loads a plain Ruby translations file. eval'ing the file must yield
         # a Hash containing translation data with locales as toplevel keys.
         def load_rb(filename)
-          translations = eval(IO.read(filename), binding, filename)
+          translations = eval(IO.read(filename), binding, filename.to_s)
           [translations, false]
         end
 
diff --git a/lib/i18n/backend/fallbacks.rb b/lib/i18n/backend/fallbacks.rb
index a88a4fca..caa4e66e 100644
--- a/lib/i18n/backend/fallbacks.rb
+++ b/lib/i18n/backend/fallbacks.rb
@@ -71,7 +71,11 @@ def resolve_entry(locale, object, subject, options = EMPTY_HASH)
 
           case subject
           when Symbol
-            I18n.translate(subject, **options.merge(:locale => options[:fallback_original_locale], :throw => true))
+            I18n.translate(subject, **options.merge(
+              :locale => options[:fallback_original_locale],
+              :throw => true,
+              :skip_interpolation => true
+            ))
           when Proc
             date_or_time = options.delete(:object) || object
             resolve_entry(options[:fallback_original_locale], object, subject.call(date_or_time, **options))
diff --git a/lib/i18n/backend/simple.rb b/lib/i18n/backend/simple.rb
index 7caa7dd1..2cac2452 100644
--- a/lib/i18n/backend/simple.rb
+++ b/lib/i18n/backend/simple.rb
@@ -10,14 +10,14 @@ module Backend
     # The implementation is provided by a Implementation module allowing to easily
     # extend Simple backend's behavior by including modules. E.g.:
     #
-    # module I18n::Backend::Pluralization
-    #   def pluralize(*args)
-    #     # extended pluralization logic
-    #     super
-    #   end
-    # end
-    #
-    # I18n::Backend::Simple.include(I18n::Backend::Pluralization)
+    #     module I18n::Backend::Pluralization
+    #       def pluralize(*args)
+    #         # extended pluralization logic
+    #         super
+    #       end
+    #     end
+    #     
+    #     I18n::Backend::Simple.include(I18n::Backend::Pluralization)
     class Simple
       module Implementation
         include Base
diff --git a/lib/i18n/tests/defaults.rb b/lib/i18n/tests/defaults.rb
index 31fdb469..e5db3365 100644
--- a/lib/i18n/tests/defaults.rb
+++ b/lib/i18n/tests/defaults.rb
@@ -47,6 +47,13 @@ def setup
         I18n.backend.store_translations(:en, { :foo => { :bar => 'bar' } }, { :separator => '|' })
         assert_equal 'bar', I18n.t(nil, :default => :'foo|bar', :separator => '|')
       end
+
+      # Addresses issue: #599
+      test "defaults: only interpolates once when resolving defaults" do
+        I18n.backend.store_translations(:en, :greeting => 'hey %{name}')
+        assert_equal 'hey %{dont_interpolate_me}',
+          I18n.t(:does_not_exist, :name => '%{dont_interpolate_me}', default: [:greeting])
+      end
     end
   end
 end
diff --git a/lib/i18n/tests/lookup.rb b/lib/i18n/tests/lookup.rb
index bbd775f0..f1bee792 100644
--- a/lib/i18n/tests/lookup.rb
+++ b/lib/i18n/tests/lookup.rb
@@ -76,6 +76,12 @@ def setup
       test "lookup: a resulting Hash is not frozen" do
         assert !I18n.t(:hash).frozen?
       end
+
+      # Addresses issue: #599
+      test "lookup: only interpolates once when resolving symbols" do
+        I18n.backend.store_translations(:en, foo: :bar, bar: '%{value}')
+        assert_equal '%{dont_interpolate_me}', I18n.t(:foo, value: '%{dont_interpolate_me}')
+      end
     end
   end
 end
diff --git a/lib/i18n/tests/procs.rb b/lib/i18n/tests/procs.rb
index 6abd8612..db99c766 100644
--- a/lib/i18n/tests/procs.rb
+++ b/lib/i18n/tests/procs.rb
@@ -57,6 +57,7 @@ def self.filter_args(*args)
           if arg.is_a?(Hash)
             arg.delete(:fallback_in_progress)
             arg.delete(:fallback_original_locale)
+            arg.delete(:skip_interpolation)
           end
           arg
         end.inspect
diff --git a/lib/i18n/version.rb b/lib/i18n/version.rb
index 7c4b3edd..546bcbaa 100644
--- a/lib/i18n/version.rb
+++ b/lib/i18n/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module I18n
-  VERSION = "1.14.5"
+  VERSION = "1.14.6"
 end
diff --git a/test/i18n/load_path_test.rb b/test/i18n/load_path_test.rb
index 7d0d27a1..ab354c08 100644
--- a/test/i18n/load_path_test.rb
+++ b/test/i18n/load_path_test.rb
@@ -31,4 +31,14 @@ def setup
     I18n.load_path << Dir[locales_dir + '/*.{rb,yml}']
     assert_equal "baz", I18n.t(:'foo.bar')
   end
+
+  test "adding Pathnames to the load path does not break YML file locale loading" do
+    I18n.load_path << Pathname.new(locales_dir + '/en.yml')
+    assert_equal "baz", I18n.t(:'foo.bar')
+  end
+
+  test "adding Pathnames to the load path does not break Ruby file locale loading" do
+    I18n.load_path << Pathname.new(locales_dir + '/en.rb')
+    assert_equal "bas", I18n.t(:'fuh.bah')
+  end
 end
diff --git a/test/i18n_test.rb b/test/i18n_test.rb
index 85679d40..642920de 100644
--- a/test/i18n_test.rb
+++ b/test/i18n_test.rb
@@ -315,6 +315,10 @@ def setup
     assert_raises(I18n::ArgumentError) { I18n.interpolation_keys(["bad-argument"]) }
   end
 
+  test "exists? given nil raises I18n::ArgumentError" do
+    assert_raises(I18n::ArgumentError) { I18n.exists?(nil) }
+  end
+
   test "exists? given an existing key will return true" do
     assert_equal true, I18n.exists?(:currency)
   end
diff --git a/test/test_data/locales/plurals.rb b/test/test_data/locales/plurals.rb
index 9dc3ef0e..6606c0dc 100644
--- a/test/test_data/locales/plurals.rb
+++ b/test/test_data/locales/plurals.rb
@@ -3,7 +3,7 @@
 {
   :af => { :i18n => { :plural => { :keys => [:one, :other], :rule => lambda { |n| n == 1 ? :one : :other } } } },
   :am => { :i18n => { :plural => { :keys => [:one, :other], :rule => lambda { |n| [0, 1].include?(n) ? :one : :other } } } },
-  :ar => { :i18n => { :plural => { :keys => [:zero, :one, :two, :few, :many, :other], :rule => lambda { |n| n == 0 ? :zero : n == 1 ? :one : n == 2 ? :two : [3, 4, 5, 6, 7, 8, 9, 10].include?(n % 100) ? :few : [11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99].include?(n % 100) ? :many : :other } } } },
+  :ar => { :i18n => { :plural => { :keys => [:zero, :one, :two, :few, :many, :other], :rule => lambda { |n| n == 0 ? :zero : n == 1 ? :one : n == 2 ? :two : (3..10).cover?(n % 100) ? :few : (11..99).cover?(n % 100) ? :many : :other } } } },
   :az => { :i18n => { :plural => { :keys => [:other], :rule => lambda { |n| :other } } } },
   :be => { :i18n => { :plural => { :keys => [:one, :few, :many, :other], :rule => lambda { |n| n % 10 == 1 && n % 100 != 11 ? :one : [2, 3, 4].include?(n % 10) && ![12, 13, 14].include?(n % 100) ? :few : n % 10 == 0 || [5, 6, 7, 8, 9].include?(n % 10) || [11, 12, 13, 14].include?(n % 100) ? :many : :other } } } },
   :bg => { :i18n => { :plural => { :keys => [:one, :other], :rule => lambda { |n| n == 1 ? :one : :other } } } },
@@ -52,7 +52,7 @@
   :ku => { :i18n => { :plural => { :keys => [:one, :other], :rule => lambda { |n| n == 1 ? :one : :other } } } },
   :lb => { :i18n => { :plural => { :keys => [:one, :other], :rule => lambda { |n| n == 1 ? :one : :other } } } },
   :ln => { :i18n => { :plural => { :keys => [:one, :other], :rule => lambda { |n| [0, 1].include?(n) ? :one : :other } } } },
-  :lt => { :i18n => { :plural => { :keys => [:one, :few, :other], :rule => lambda { |n| n % 10 == 1 && ![11, 12, 13, 14, 15, 16, 17, 18, 19].include?(n % 100) ? :one : [2, 3, 4, 5, 6, 7, 8, 9].include?(n % 10) && ![11, 12, 13, 14, 15, 16, 17, 18, 19].include?(n % 100) ? :few : :other } } } },
+  :lt => { :i18n => { :plural => { :keys => [:one, :few, :other], :rule => lambda { |n| n % 10 == 1 && !(11..19).include?(n % 100) ? :one : [2, 3, 4, 5, 6, 7, 8, 9].include?(n % 10) && !(11..19).include?(n % 100) ? :few : :other } } } },
   :lv => { :i18n => { :plural => { :keys => [:zero, :one, :other], :rule => lambda { |n| n == 0 ? :zero : n % 10 == 1 && n % 100 != 11 ? :one : :other } } } },
   :mg => { :i18n => { :plural => { :keys => [:one, :other], :rule => lambda { |n| [0, 1].include?(n) ? :one : :other } } } },
   :mk => { :i18n => { :plural => { :keys => [:one, :other], :rule => lambda { |n| n % 10 == 1 ? :one : :other } } } },
@@ -61,7 +61,7 @@
   :mo => { :i18n => { :plural => { :keys => [:one, :few, :other], :rule => lambda { |n| n == 1 ? :one : n == 0 ? :few : :other } } } },
   :mr => { :i18n => { :plural => { :keys => [:one, :other], :rule => lambda { |n| n == 1 ? :one : :other } } } },
   :ms => { :i18n => { :plural => { :keys => [:other], :rule => lambda { |n| :other } } } },
-  :mt => { :i18n => { :plural => { :keys => [:one, :few, :many, :other], :rule => lambda { |n| n == 1 ? :one : n == 0 || [2, 3, 4, 5, 6, 7, 8, 9, 10].include?(n % 100) ? :few : [11, 12, 13, 14, 15, 16, 17, 18, 19].include?(n % 100) ? :many : :other } } } },
+  :mt => { :i18n => { :plural => { :keys => [:one, :few, :many, :other], :rule => lambda { |n| n == 1 ? :one : n == 0 || (2..10).include?(n % 100) ? :few : (11..19).include?(n % 100) ? :many : :other } } } },
   :my => { :i18n => { :plural => { :keys => [:other], :rule => lambda { |n| :other } } } },
   :nah => { :i18n => { :plural => { :keys => [:one, :other], :rule => lambda { |n| n == 1 ? :one : :other } } } },
   :nb => { :i18n => { :plural => { :keys => [:one, :other], :rule => lambda { |n| n == 1 ? :one : :other } } } },