Stock markets have over 100 years of booms, busts and crashes. It's likely to continue. Even if there is never another bear market or crash, we don't know that, so the rational strategy is to build a portfolio that can withstand a crash with a level of volatility that you can stand, and educate yourself on typical market movements and prepare yourself for if/when it happens.
It is helpful to look at history to understand how the stock market recovers from corrections and bear markets:
May 1946 to May 1947. Stocks plunge 28.4%.
June 1948 to June 1949. Stocks decline 20.6%.
June 1950 to July 1950. Stocks fall 14%.
July 1957 to October 1957. Stocks fall 20.7%.
January 1962 to June 1962. Stocks plunge 26.4%
February 1966 to October 1966. Stocks fall 22.2%.
February 1966 to October 1966. Stocks fall 22.2%.
November 1968 to May 1970. Stocks plunge 36.1%.
April 1973 to October 1974. Stocks plunge 48%
September 1976 to March 1978. Stocks fall 19.4%.
February 1980 to March 1980. Stocks fall 17.1%.
November 1980 to August 1982. Stocks fall 27.1%.
August 1987 to December 1987. Stocks fall 33.5%.
July 1990 to October 1990. Stocks fall 19.9%.
July 1998 to August 1998. Stocks fall 19.3%.
March 2000 to October 2002. Stocks plummet 49.1%.
November 2002 to March 2003. Stocks fall 14.7%
October 2007 to March 2009. Stocks plummet 56.8%.
April 2011 to October 2011. Stocks fall 19.4%.
June 2015 to August 2015. Stocks fall 11.9%
Stocks gained +1,100-fold during this 70-year period.
Source:
http://www.fool.com/investing/general/2015/09/09/keep-in-mind-stocks-rose-1100-fold-during-this-per.aspxLesson learned: Stay-the-Course