For example, just because you feel healthy may not necessarily mean your are healthy. You may be active one day and the next day you find that you have a malignant tumor. Detecting the problem early can make a life and death difference. Parents assume that their children are doing well in school until they find, sometimes too late, that their children have been on drugs, mixing with bad company, committing crimes, etc. Some bosses think that their key workers are honest until they discover that some have absconded with funds.
Some assumptions are harmless, but others are risky.
Spare a moment to sit back, think and reflect about what's going on around you. Be more proactive and observant. Get more facts. The extra effort could make life happier for you. Peter Ling, Thoughts for Effective Living.