Interested in Language
Can anyone explain the difference between proposal and proposition and when you should use each of them?
If you are speaking to an aquaintance or colleague regarding an idea for a business or something that you think he/she might be interested in, you would say "I have a proposition to make to you."
If your friend is very interested in joining in a business with you, you would say "I will send you a written proposal of how I think this could go forward."
Proposal is more formal, and generally written.