Continuous distribution additivity contradiction?

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If a random variable $X$ is continuous, then by definition, $$(1) \quad P(X=x) = 0, \forall x \in \mathbb{R}\,.$$ Also, by additivity, $$(2) \quad P(X \le c) = \sum_{x \in \mathbb{R} \le c} P(X = x)\,.$$ Doesn't $(1)$ imply that $(2)$ must equal $0$?