How does Jean-Paul Sartre argue that existentialism can still offer our lives meaning in his lecture, ‘Existentialism is a Humanism’?

How does Jean-Paul Sartre argue that existentialism can still offer our lives meaning in his lecture, ‘Existentialism is a Humanism’?

Do you find Sartre’s argument convincing? Do you think existentialism is capable of providing the basis for meaning

1800-2000 word essay adressing all questions in the title, please reference the text attached, and use any infomation you can find, but only reference them if they are from a book or paper (not websites)