There's never a new fashion but it's old.

I think that the author of this quote is trying to tell us that theres nothing that hasnt been done before. That even though you think that you are being original somewhere out there someone has already done it and that we have to anticipate it. There were only so many options we were given and in the however many years we've been in existance our predeccesors have already done it so i think that he thinks that we should all just calm down and not take life so seriously anymore because it has all been done before.