Shortcuts and formatters

There are several things that are not required by require "reality" (but are included in interactive console).

Pretty inspect: require "reality/pretty_inspect" redefines #inspect method for some Ruby core classes, which are heavily utilized by reality, and their default #inspect is not that pretty. For example:

# without pretty_inspect
Reality::Entity('Yukihiro Matsumoto').birthday
# => #<Date: 1965-04-14 ((2438865j,0s,0n),+0s,2299161j)>

# with pretty_inspect
Reality::Entity('Yukihiro Matsumoto').birthday
# => #<Date: 1965-04-14>

# without pretty_inspect
Reality::Entity('Buenos Aires').population / Reality::Entity('London').population
# => (2890151/8416535)
# ↑ it's Rational, pretty precise, but hard to read

# with pretty_inspect
Reality::Entity('Buenos Aires').population / Reality::Entity('London').population
# => 0.3
# ↑ it's still the same Rational, but with less precise/more readable output

Shortcuts: require "reality/shortcuts" provides you with pretty concise syntax:

include Reality

E('Yukihiro Matsumoto')

L('Argentine', 'Bolivia', 'Chile')

Also, you could do include Reality::Methods (instead of include Reality) in your code to not pollute your namespace with anything except Entity and List methods (E and L is also in this namespace after you have required "reality/shortcuts").