The economy reeled this summer from the impact of a series of adversities. The most important was the shortage of motor fuel resulting from the disruption of oil supplies from Iran. Others included truck strikes, the airline strike, labor pacts that exceeded Administration guides, soaring interest rates, further price inflation, and still lingering effects of the severe winter. Together, these blows brought an end to a four-year upswing, an expansion already creaky with age by historical standards. Belated recognition of the fact that oil shortages are likely to recur is having a profound effect on patterns of consumer spending, business investment, and real estate development. Rethinking of broad strategies means delays in decision-making and a more sluggish economy.