This a good read especially at times like this.
"A contrarian investor believes the people who say the market is going up do so only when they are fully invested and have no further purchasing power. At this point, the market is at a peak; when people predict a downturn, they have already sold out, at which point the market can only go up."
Read more:
https://www.investopedia.com/articles/financial-theory/08/contrarian-investing.asp