The logic behind higher highs and lower lows is a basic technical analysis principle used to determine the trend of an asset, such as a stock or a currency.

A higher high refers to a situation where the current high of an asset is greater than the previous high. This indicates that the trend is bullish and that the price of the asset is rising. On the other hand, a lower low refers to a situation where the current low of an asset is lower than the previous low. This indicates that the trend is bearish and that the price of the asset is falling.

When higher highs and higher lows are present, it is a clear indication of an uptrend, meaning that the price of the asset is rising and is expected to continue to rise. On the other hand, when lower lows and lower highs are present, it is a clear indication of a downtrend, meaning that the price of the asset is falling and is expected to continue to fall.

Higher highs and lower lows can be identified by analyzing the price action of an asset over a specified period of time, such as a day, a week, or a month, and plotting the high and low prices on a chart.