Answer:
Economics is the study of how individuals make decisions under conditions of scarcity and its concepts are heavily based on experimental and empirical data, not the subjective conclusions made through value judgements. Value judgements are based on personal opinions that judge the rightness and the wrongness of matters and this is an approach that cannot be applied to economics. Economics does not take on this approach and relies on the experimental and empirical data that is available objectively.
Similarly, a science is anything that proposes a theory (or hypothesis) and tests the theory to make a conclusion about the matter, based on experimental evidence that supports the hypothesis. Economics is basically this. Economists propose theories about both individual behaviour (microeconomy) and the behaviour of the aggregate economy (macroeconomy) and tests them by applying them to real-life situations. Therefore, economics is a science and its discipline is not based on value judgements.